Phonograph control system



2, 1941. 1.. D. NORTON PHONOGRAPH CONTROL SYSTEM Filed April 21, 1939 INVENTOR Leland D. Ivorian Patented Dec. 2, 1941 UNITED STATES PATENT OFFICE PHONOGRAI'H CONTBOL'SYSTEM Lelandll.Norton,Bridgeport, Conn assignorto Dictaphone Corporation, New York, N. Y., a corporation of New York Application April 21, 1939, Serial No. 269,081

, e e 6 Claims. This invention relates to dictating machines and more particularly to portable dictating machines adaptable for operation from any of the customarily available sources of electrical Due to the quick tempo of modern times business men, lawyers, authors, and other persons who have occasion to do considerable dictating, frequently find it necessary or desirable to use a dictating machine in places other than their homes or oihces. Thus. they require a dictating machine which will operate on any available source of electric power, such, for example, as the 220volt or llo-volt alternating current or direct current commercial power lines, 32-volt storage'battery systems encountered in farm lighting or railway lighting, or 6- or l2-volt' storage battery systems usually available in automobfles or small boats. In the past this problem has been solved by using several dictating machines, each one provided with a motor suitable for operation on the particular voltage available in the ofllce, train. automobile, boat,

etc or by using a standard dictating machine with llo-volt motor, connected to a motor generator set having a low voltage driving motor, for example, a 6-volt motor for operation from an automobile storage battery. None of these arrangements are particularly satisfactory because they are complicated, inemcient, and costly.

In accordance with the present invention, this problem has been solved by providing a dictating machine with a universal motor unit capable of operating from any of the usually available electrical power supplies. This universal drivingunitrequiresaminimumofpartaandonly a few simple adjustments are necusary to adapt it for operation on any usually available power supply. This is accomplished by providing a motor having a commutated armature and a field winding connected in a circuit with a switching arrangement and an adjustable series impedance so that the field winding may be connected in shunt across the armature when it is desired to operate the dictating machine on low voltage sources such as a B-volt storage battery, or so that the field winding may be connected in series with the armature and the adjustable impedance when it is desired to operate the dictating machine on higher voltages such as the usual llo-volt power supply.

It is an object of this invention, therefore, to provide a control system for a portable dictating machine having a universal motor, adapted simply and eflicientiy to control the operation of said machine with any of the usually available sources of electrical power. Other-objects will be in'part' obvious and in part pointed out hereinafter,

For a further disclosure of the invention referonc may be had tothe following description and the accompanying drawing, in which:

Figure 1 shows in perspective a'commercial dictating machine embodying the invention; and

Figure 2 is a schematic wiring diagram of the present control system employed with the dictating machine shown in Figure 1.

Referring to Figure l, a universal driving motor 1, is suitably mounted inside a housing 4 supporting a dictating machine. The motor 2, by means of a pulley 8 mounted on one end of the motor drive shaft 8. a belt ii, a pulley ll, and a clutch mechanism, not shown. drives a record supporting mandrel II which is mounted on a shaft ll suitably iournaled on the frame I of the machine.

The usual tone arm II and sound box II are mounted on a carriage 22 which is moved along a guide bar 24 in a path parallelto the record surface by means of a feed screw driven from mandrel shaft II by suitable gears. not shown, whenever the record supporting mandrel I0 is rotated. A control lever 2|, shown in its neutral position, is provided on the carriage 22 for conditioning the sound box 2| for recording, reproducing. or to be inoperative or neutral. The movement of this lever II to position the sound box is transmitted through a suitable link and lever system, not shown, to a suitable switch I! connected in the circuit to control a signal buzzer N in the manner described in United States Patent No. 1,989,783, so that the bumer gives a warning signal upon closure of the motor circuit with the sound box I conditioned otherwise than for recording.

The tone arm I. is connected by means of a flexible speaking tube it (shown partially broken away) to a mouthpiece 4|. The mouthpiece carries a control button I! which is connected by means of a Bowden wire, not shown, passing through the speaking tube 10 to clutchoperating mechanism, not shown. This clutchoperating mechanism effects connection of the large pulley It with the-mandrel shaft I. to start and stop the rotation of the mandrel I. in respons to depression and release of control button 42.

The end of the speaking tube 38 and the mouthpiece ll are adapted to rest on a pivoted snap-switch ll, mounted on 7 *ing 4, is adapted to condition the circuit for low voltage operation when thrown to the right and a II, respectively. The

ll. Conductor II the neutral or middle ,irom, the varmature It are hanger arm I when the machine is not in use. This arm 44 is connected through a link and lever arrangement 46 to a snap-acting switch ll which is connected in the power supply circult to the machine motor.

A centrifugal governor I. is attached to the drive shaft 8 of the motor 2, and an adjustment mechanism-l2 is provided for adjusting the speed maintained by this governor. A Ian I isalso at- A three-way receptacle It is mounted in the back of housing l for connecting the instrument to the power supply. A double-poledouble-throw the front oi the housior high voltage operation when thrown to the left.

The driving motor 2 (see 2 is providedwith a hold winding It, and an armature it with circuittn adaptit nected to two or the contacts of a three-way plus II adapted to coact with the three-way receptacle "mounted on the back oi housing 4 of the dictating machine. Thus a connection is made between the two wires of cable 88 and contacts I. and ll of the receptacle ll.

11' the machine is to be operated on some lowvoltage source of electrical power such as a 6- or iz-volt storage battery, connection is made between this source 01' power and the machine by means oi a cord and plug rrangement. generally indicated at ll, and comprising a bayonet type connector 02, adapted to iit into a bayonet type socket oi the kind usually employed in automobiles or boats, which is connected to one end oi a two-wire cable 04. The two wires at the other end of this cable N are so connected to two or the contacts on a three-way plug ll, that when I! so that the cable u may be connected its associated commutatorand brushes N. The

speciiic form of the armature and iield structures, the number of turns in'the coils, the size of the wire used, thenumber of commutator bars and brushes, and other details oi the design or motor I depend upon the speed and power desired and upon the particular range of voltages through which the motor is to be operated.

The arrangement whereby these various electrical elements of the dictating machine are connected soas to permit its universal operation on almost any usually available commercial source of power may be-more readily understood by reierrins to Fi u e 2. w i h ing diagram oi the various circuit elements. The connections to theiield 6 2 and the armature N are brought out of the motor, separately by means shows a schematic wir-' of conductors. and, and conductors II and conductors I! and I! from the held 62 are connected to the center poles I2 and II of the double-pole double-throw switch from one side oi the armature N is connected to a pole It on one side of the on the other side of the switch. from theother side of the armature N is connected to a pole II on the same side of the switch as pole ll; Conductor II is also connected through a wire is and the main power switch 48 contact II on the repole It,-and conductor I. connected through a wire II to one or. the other ceptacle It. The-remaining on the, same side of the Conductor II ceptacle. l8. Pole ll.

pole 11 or switch ll, switch as pole It and I diagonally opposite pole II, is connected through a wire I! and the current-limiting adjustable rea sister II, to the third contact It on the receptacle il. The buzzer l4 and its control switch 32 are connected to wires II and II, thus putting it di- IV or rectly across the armature N. A condenser 84 power supply plug it connected toone end of a two-wire cable II, the other contacts ti on re-' end of which is con-' I I switch it and to the diagonally opposite pole II plug 90., Switch 4 is I because. the.

thisplug is inserted in the receptacle II on the dictating machine,

contact is made between the two wires of cable It and contacts II and II of this receptacle N. I! desired, a pair of battery clips may be substituted for the bayonet type lug directly to the electrodes oi cables at and It are preferably secured to each other by some suitable means such as clamp it near the three-way plugs ill and O8 so -that they will always be together and with the machine, and so available when either low voltage or high voltage operation is desired. 7 I V 'When it is desired to operate the dictating Innon a'high voltage such as 110 volts, plug 90 is plugged into the receptacle It. When the double-pole double-throw switch II is thrown to the left or high voltage side, this connects the iield I2 inseries with armature t4 and resistor It across the power supply, and the motor 2 cperates as a series motor. 'l'heresistorlt is set at a value dependent'upon the line voltage and upon whether this voltage is A. C. or D. C. A sreater amount of resistance the line voltage is high. Likewise, ii the motor operating on D. C. more resistance is required inductive reactance oi the motor is inefl'ective as an impedance in D. C. operation. .With whenever the master switch It is closed by removing the speaking tube from hook ll.

Ii it is desired to operate the machinecn a low-voltage source, such as a 6-volt storage battery, plug "is inserted into a suitable outlet to which the storage battery is connected, and plug so is inserted in receptacle "instead of CI is thrown to theright or low voltage connection. This operation, connects the armature N in parallel with the field standard two prong 62, andthe motor 2 then operates as a lowvoltage shunt motor when themasterswitch II is closed. With. either the high nection, the buzzer 34 is or the low voltage conalways connected across the armature and operates whenever switch 32 is closed, as, for example, when the, instrument is not properly conditioned for recording.

Inasmuch as the voltage across the armature M variesover a comparatively wide range. depending on-whether the motor is operating as a series or shunt motor, or on A. C. or D. C., acondenser 84 is connected across the contacts of the buzer 34 to prevent sparking between the contacts over the higher ranges of armature voltage.

This arrangement provides a simple and foolproof means for operating a dictating machine a storage battery. 'Thesetwo is required in the. circuit it this arrangement, the motor will start ing and said armature winding toconnectsaidfirstcircuittoa source, and means to connect said second to a low voltage source.

a,ses,see

on electrical power sources various voltages, anyoneoiwhichmaychancetobetheonly source of power available for operation. The only manipulation necessary is to use the cord and plug corresponding to the source of voltage to be used and to operate the double-pole doublethrow switch 6..

It should be noted that it is not possible to injure the motor 2 by having the switch 0 in the wrong position because of the novel circuit arrangement and because of the three-way receptacle I which is designed to receive the plugs II and 96 in only one position. For example, it switch I is thrown to the right or low voltage position, and the high voltage cord and plug II are connected to receptacle It, the motor will not o erate because there is no power source connected to contact ll of receptacle I and contact ll of the receptacle II is merely connected to the disconnected pole 11 or switch 8|. A similar situation exists it the low voltage cord and plug arrangement 8! is used and the switch II is in its left-hand or high voltage position. In that case no power source is connected to. contact II of receptacle ll.

As many possible embodiments of the present invention may be made without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawing is to be interpreted as illustrative only and not in a limiting sense.

I claim:

1. In apparatus of the character described in which it is desirable to operate a driving motor at constant speed from either a high voltage or a low voltage source 0! electric power, in combination, a field winding, an armature winding. a wiring and switching assembly comprising, switch means, means constituting a first circuit which is completed by operating said switch means to connect said field windin and said armature winding in series. means constituting a second circuit which is completed by operating said switch means to connect said field windin parallel, means high voltage circuit said first connector, and said means connecting 2. The combination according to claim 1 wherein said switch means is a two-position switch which assumes a first position to complete said first circuit and a second position to complete said second circuit. Y

3. The combination according to claim 1 wherein an electric signa1 device safely operable only within a limited voltage range, and a signal control switch, are connected in series across said armature winding at all times whereby said signal is always safely operable whether said motor apparatus is connected to said high voltage source or said low voltage source.

4. The combination according to claim 1 wherein said high voltage source supplies power at approximately volts and said low voltage source supplies power at approximately 6 volts, and a predetermined impedance is provided in said first circuit.

5. The combination according to claim 1 wherein said first and second circuits have a first connection common to said high and low voltage sources and second and third connections individual respectively to said sources, and a motor control switch provided in said common connection.

6. The combination according to claim 1 wherein the first and second terminals of a triple terminal contact device are connected in said first circuit, the first and third terminals of said device are connected in said second circuit, said means connecting said first circuit to said high voltage source comprises a first triple terminal connector adapted to coact with said contact device in one position only and a double conductor cable connected to said high voltage source and the first and second terminals oi said second circuit to said low voltage source comprises a second connector similarto said first connector and a second double conductor cable connected to said low voltage source and the first and third terminals of said second conhector.

LELAND D. NORTON. 

